From owner-freebsd-net Tue May 30 2: 5: 4 2000 Delivered-To: freebsd-net@freebsd.org Received: from sasi.com (sasi.com [164.164.56.2]) by hub.freebsd.org (Postfix) with ESMTP id 276AC37BD79; Tue, 30 May 2000 02:04:41 -0700 (PDT) (envelope-from gbnaidu@sasi.com) Received: from samar (sasi.com [164.164.56.2]) by sasi.com (8.9.3/8.9.3) with SMTP id OAA05884; Tue, 30 May 2000 14:32:35 +0530 (IST) Received: from sund6.sasi.com ([10.0.16.6]) by sasi.com; Tue, 30 May 2000 14:32:33 +0000 (IST) Received: from localhost (gbnaidu@localhost) by sund6.sasi.com (8.9.3/8.9.1) with ESMTP id OAA21093; Tue, 30 May 2000 14:32:30 +0530 (IST) Date: Tue, 30 May 2000 14:32:30 +0530 (IST) From: "G.B.Naidu" To: "Koster, K.J." Cc: freebsd-hackers@FreeBSD.org, freebsd-net@FreeBSD.org Subject: RE: system hangs... In-Reply-To: <59063B5B4D98D311BC0D0001FA7E4522026D75BE@l04.research.kpn.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Hi, Please see my comments below: On Tue, 30 May 2000, Koster, K.J. wrote: > > > > We have made some kernel changes. And accordingly we are > > testing the changes using some user level daemon. After > > sending some packets, the system hangs. The number of > > packets sent before the system hangs varies from time to > > time. > > > What kind of changes? What kind of packets? What kind of deamon? What kind > of kernel? We are trying to implement MPLS on FreeBSD. so we are implementing forwarding tables in side the kernel. The chamges are done in ip_output() and ether_output(). We have added some more routing messages and corresponding functions. Dameon we are running is LDP daemon. The packets We are sending to test are ping packets. Kernel version is 3.3-RELEASE > > > > > Could some body tell me how to know what is happening? How > > do I find out the reason for hanging? Is there anyway to get > > such information through some core dump? I have enabled > > taking dumps and it is dumping when the system panics but > > not when it hangs. > > > You can make the system panic manually, and then you have your kernel core. I am concerned about hangs not panic. If it hangs, I cant type even enter. Nothing responds except the reset and power off key. SO is there a way I can take core dumps when the system hangs? > > As for how to know what's happening: printf() is your friend. > Is there a way to redirect the out put of printf() statements into /var/log/messages file? How do I do that? > > > > Is memory leakage can cause a system hang? If so how do I > > find out that there is a memory leakage? > > > There are many good books and web sites that cover basic debugging > techniques. Could you please give me some pointers to these locations and books? I would be glad to know those locations where I can get some debug techniques. > > You have to provide a *lot* more information than this. We can only help you > if you are able to produce some detailed description of your problem. If you > can't tell sitting behind the box, how are we supposed to know what you've > done wrong? If you need any more information, please let me know. The problem is because the system hangs, I cant do anything to find out what's happening. thanks a lot --gb > > Kees Jan > > ============================================== > Everyone is responsible for his own actions, > and (people tend to forget this) the effect > they have on others. > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message